In addition to the ingredients indispensable for the washing process, such as surfactants and builder materials, detergents generally also contain further constituents, which can be summarized under the term washing auxiliaries and which comprise active ingredient groups as diverse as those such as foam regulators, anti-graying agents, bleaching agents, bleach activators, and dye transfer inhibitors. Auxiliaries of this type also include substances which give the laundry fibers dirt-repelling properties and which, if present during the washing process, support the dirt-repelling capability of the other detergent constituents. The same is also true, analogously, for cleaning products for hard surfaces. Dirt-repelling substances of this type are often referred to as “soil release” active ingredients or, on account of their ability to make the treated surface, for example the fibers, dirt-repelling, are referred to as “soil repellents”. For example, the dirt-repelling effect of methyl cellulose is known from US patent U.S. Pat. No. 4,136,038. European patent application EP 0 213 729 discloses the reduced redeposition with use of detergents that contain a combination of soap and non-ionic surfactant with alkyl hydroxyalkyl cellulose. Textile treatment agents which contain cationic surfactants and non-ionic cellulose ethers with HLB values of from 3.1 to 3.8 are known from European patent application EP 0 213 730. US patent specification U.S. Pat. No. 4,000,093 discloses detergents that contain 0.1 wt. % to 3 wt. % of alkyl cellulose, hydroxyalkyl cellulose, or alkyl hydroxyalkyl cellulose, and 5 wt. % to 50 wt. % of surfactant, wherein the surfactant component consists substantially of C10 to C13 alkyl sulfate and up to 5 wt. % of C14 alkyl sulfate, and less than 5 wt. % of alkyl sulfate with alkyl groups of C15 and higher.
Due to their chemical similarity to polyester fibers, particularly effective soil release active ingredients in textiles made of this material are copolyesters containing dicarboxylic acid units, such as terephthalic acid or sulfoisophthalic acid, alkylene glycol units, such as ethylene glycol or propylene glycol, and polyalkylene glycol units, such as polyethylene glycol. Soil release copolyesters of the aforesaid type and use thereof in detergents have long been known.
The polymers known from the prior art have the disadvantage that they do not have any efficacy, or have only inadequate efficacy in particular in textiles that are not made of polyester, or are not made primarily of polyester. A large amount of modern textiles, however, are made of cotton or cotton-polyester blended fabrics, and there is thus a need for soil release active ingredients that have improved efficacy in particular in the case of grease stains in particular on textiles of this kind.
It has surprisingly been found that this problem can be solved by the use of certain cellulose derivatives.
International patent application WO 00/18860 A1 discloses the rebuilding effect of what are called cellulose esters in that document, which can also be cellulose carbamates, on textiles. This is supposedly based on the fact that the cellulose esters are deposited on the damaged textile areas, react with the fibers by cleaving of the reactive ester functionality, and thus strengthen the damaged areas by cellulose. It is known from international patent application WO 00/18861 A1 that cellulose esters of this kind increase the affinity of material to be deposited on a substrate, such as a fiber, for said substrate. International patent application WO 01/72937 A1 relates to the reduction of dye losses when laundering dyed textiles by virtue of the use of cellulose esters of this kind. International patent application WO 01/72944 A1 discloses the suitability of cellulose ethers of this kind to increase the deposition of fragrances on textiles, and it is known from patent application GB 2 360 791 A that they contribute to fabric softness by virtue of their deposition on textiles.